#!/usr/bin/perl
use warnings;
use strict;
use Inline C=>'DATA';

my @array = ( 1 .. 100 );

print get_an_element(\@array)."\n";

__DATA__
__C__

SV* get_an_element(SV* aref)
{

AV* array;

if (! SvROK(aref))
croak("aref is not a reference");

array = (AV*)SvRV(aref);

SV** v = av_fetch(array,8, 0);
if( v == NULL )
   croak("not enough elements in array");
   
SV* ret = *v;
SvREFCNT_inc(ret);

return ret;
}
__END__

##</code><code>##

#!/usr/bin/perl
use warnings;
use Tk;
use Inline C;
use strict;

$| = 1;

my $mw   = tkinit;

$mw->Button(
    -text    => 'Get Array from C',
    -command => sub {
                &get_data();
         })->pack();

$mw->Button(
    -text    => 'Quit',
    -command => sub { exit; })->pack();

MainLoop;
########################################

sub get_data {
        my $freq_adj = .1;
        my $vol = .5;
	my @raw = gen($freq_adj, $vol);  
	#print "@raw\n\n";

        foreach(@raw){
        print $_,"\n";
	}

}
__END__
__C__
#include <stdio.h>
#include <math.h>

/* function must return void for Inline to use the stack 
   See the Inline_C cookbook
*/

void gen(float freq_inc , float vol)
{
    /* two numbers to work with */
    float result, rad; 
    rad = .1;
    
Inline_Stack_Vars;
Inline_Stack_Reset;
    
 while ( rad < 6.3 ) {
        rad = rad + freq_inc;
        result =  vol * 32768 * sin(rad);
        Inline_Stack_Push(sv_2mortal(newSVnv(result)));
      /*  newSVnv for floats, newSViv for ints, see perldoc perlguts */
      }

Inline_Stack_Done;
 
}

##</code><code>##

#!/usr/bin/perl
use warnings;
use Tk;
use Inline C;
use strict;

$| = 1;

#this ones returns ints, not floats

my $mw   = tkinit;

$mw->Button(
    -text    => 'Get Array from C',
    -command => sub {
                &get_data();
         })->pack();

$mw->Button(
    -text    => 'Quit',
    -command => sub { exit; })->pack();

MainLoop;
######################################

sub get_data {
        my $freq_adj = .1;
        my $vol = .5;
	my @raw = gen($freq_adj, $vol);  
	print "@raw\n\n";
}

__END__
__C__
#include <stdio.h>
#include <math.h>

/* function must return void for Inline to use the stack 
   See the Inline_C cookbook
*/

void gen(float freq_inc , float vol)
{
    /* two numbers to work with */
    float result, rad; 
    rad = .1;
    
Inline_Stack_Vars;
Inline_Stack_Reset;
    
 while ( rad < 6.3 ) {
        rad = rad + freq_inc;
        result = vol * 32768 * sin(rad);
       /* printf("%6.6f\n",result);	*/
       Inline_Stack_Push(sv_2mortal(newSViv(result)));
      }

Inline_Stack_Done;

}

##</code><code>##

#!/usr/bin/perl
use warnings;

# by Tachyon of perlmonks
# The easiest way to access arrays and hashes when you 
# are using Inline C or XS is to pass by reference and 
# use the access macros to get at the values. Here is a 
# trivial example to get you started.

use Inline 'C';

print multiply( [ 1,2,3,4 ] );

__END__
__C__

double
multiply( SV * terms )
{
I32 numterms = 0;
int i;
double result;

/* Make sure we have an array ref with values */
if ((!SvROK(terms))
|| (SvTYPE(SvRV(terms)) != SVt_PVAV)
|| ((numterms = av_len((AV *)SvRV(terms))) < 0))
{
return 0;
}

/* Set result to first value in array */
result = SvNV(* av_fetch((AV *)SvRV(terms), 0, 0));

for (i = 1; i <= numterms; i++) {
result *= SvNV(* av_fetch((AV *)SvRV(terms), i, 0));
}
return result;
}